13. Program Support Functions
13.15 High-accuracy Control ; G61.1, G08
408
Pre-interpolation acceleration/deceleration
Acceleration/deceleration control is carried out for the movement commands to suppress the
impact when the machine starts or stops moving. However, with conventional post-interpolation
acceleration/deceleration, the corners at the block seams are rounded, and path errors occur
regarding the command shape.
In the high-accuracy control function mode, acceleration/deceleration is carried out before
interpolation to solve the above problems. This pre-interpolation acceleration/deceleration enables
machining on a machining path that more closely follows the command.
The acceleration/deceleration time can be reduced because constant inclination acceleration/
deceleration is carried out.
(1) Basic patterns of acceleration/deceleration control in linear interpolation commands
Acceleration/deceleration
waveform pattern
Normal mode
Time
clamp
G1tL
G1tL
Sp
ee
d o
f ea
ch
axi
s
Time
clamp
G1t1
G1t1
S
p
e
ed
of e
a
c
h
a
xi
s
(a) Because of the constant time constant
acceleration/deceleration, the rising
edge/falling edge of the waveform becomes
more gentle as the command speed
becomes slower.
(b) The acceleration/deceleration time constant
can be independently set for each axis.
Linear type, exponential function type, or
both can be selected.
Note that if the time constant of each axis is
not set to the same value, an error will occur
in the path course.
#2002 clamp : G01 clamp speed
#2007 G1tL
: Linear type acceleration/
deceleration time constant
#2008 G1t1
: Exponential type acceleration/
deceleration time constant
High-accuracy
control mode
Time
clamp
G1btL
G1btL
G1btL/2
G1bF
G1bF/2
Com
bi
ned s
peed
G1btL/2
(a) Because of the constant inclination type
linear acceleration/deceleration, the
acceleration/deceleration time is reduced as
the command speed becomes slower.
(b) The acceleration/deceleration time constant
becomes one value (common for each axis)
in the system.
#2002 clamp : G01 clamp speed
#1206 G1bF : Target speed
#1207 G1btL : Acceleration/deceleration time
to target speed
(Note)
G1bF and G1btL are values for specifying
the inclination of the acceleration/
deceleration time; the actual cutting feed
maximum speed is clamped by the
"#2002 clamp" value.